A study was conducted looking at risk factors for HIV infection among intravenous drug users enrolled in a methadone program. The data given below were presented regarding the presence of HIV antibody among 120 non-Hispanic white subjects by total family income as assessed by blood testing at one point in time.
Group Total Family Income Number of HIV-positive Total
A <10,000 13 72
B 10,000-20,000 5 26
C >20,000 2 22
(a) What test can be used to assess if total family income is related in a consistent manner to percentage of HIV positive?
(b) Implement the test and report a p-value.
this solution discusses the test that could be used for the given data, and implements the test while reporting a p-value.